Chapter XVI.—SHAPING AND PLANING MACHINES.
The office of the shaping machine is to dress or cut to shape such surfaces as can be most conveniently cut by a tool moving across the work in a straight line.
The positions occupied among machine tools at the present time by shaping and planing machines are not as important as was the case a few years ago, because of the advent of the milling machine, which requires less skill to operate, and produces superior work.
All the cutting tools used upon shaping and planing machines have already been described with reference to outside tools for lathe work, and it may be remarked that a great deal of the chucking done on the shaping and planing machine corresponds to face plate chucking in the lathe. Both shaping machines and small planing machines, however, are provided with special chucks and work-holding appliances that are not used in lathe work, and these will be treated of presently. On large planing machines chucks are rarely used, on account of the work being too large to be held in a chuck. Shaping machines are also known as shapers and planing machines as planers.
Fig. 1496.
The simplest form of shaping machine, or shaper as it is usually termed in the United States, is that in which a tool-carrying slide is reciprocated across the work, the latter moving at the end of each back stroke so that on the next stroke the tool may be fed to its cut on the work. [Fig. 1496] represents a shaper of this kind constructed by Messrs. Hewes and Phillips, of Newark, New Jersey, in which p is a cone pulley receiving motion from a countershaft, and driving a pinion which revolves the gear-wheel q, whose shaft has journal bearing in the frame of the machine. This shaft drives a bevel pinion gearing with a bevel-wheel in one piece with the eccentric spur-wheel s, which is upon a shaft having at its lower end the bevel-wheel b to operate the work-feeding mechanism. s drives an eccentric gear wheel r, fast upon the upper face of which is a projection e, in which is a T-shaped groove to receive and secure a wrist or crank pin which drives a connecting rod secured to the slide a by means of a bolt passing through a, and secured to the same by a nut d.
When the gear-wheel r revolves, the connecting rod causes slide a to traverse to and fro endways in a guideway, provided on the top of the frame at x. On the end of this slide is a head carrying a cutting tool t, which, therefore, moves across the work, the latter being held in the vise v, which is fast upon a table w upon a carriage saddle or slider p, which is upon a horizontal slide that in turn fits to a slide vertical upon the front of the machine, and may be raised or lowered thereon by means of an elevating screw driven by a pair of mitre-wheels at f. The slider and table w (and therefore the vise and the work) are moved along the horizontal slide to feed the work to the tool cut as follows. A short horizontal shaft (driven by the bevel pinions at b), drives at its outer end a piece c, having a slot to receive a crank pin driving the feed rod n, which operates a pawl k engaging a ratchet wheel which is fast upon the horizontal screw that operates slider p.